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Greenhouse Gas Emissions fromAviation and Marine Fuel Use

Gail BrussAnd

Wiley Barbour

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Introduction

What this session will cover:– The process and the assumptions used to derive the

1998 potential Carbon Dioxide (CO2) emissions fromUnited States aviation and marine fuel usage and theportion attributed to bunker fuel

– Specifically the portion of military aviation andmarine International Bunker Fuel as firstreported in 1998

• Inventory of United States GHG Emissions and Sink,1990-1998 EPA 236-R-00-001

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Background

In 1992 the Framework Convention on ClimateChange (FCCC) was adopted.– Article 4 of the FCCC includes the commitment of the

Parties to prepare national greenhouse gas (GHG)inventories

U.S. has done inventory work for the last 10 years.First published a nation GHG inventory in 1994– Large undertaking– Estimates from all sectors of the economy

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U.S. GHG Emissions1990 -1998

0

200

400

600

800

1000

1200

1400

1600

1990 1992 1994 1996 1998

CO2CH4N2OHFC, PFC,SF6

GH

G E

mis

sion

s in

MM

TCE

1991 1993 1995 1997 1999

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U.S. GHG Emissions and Sinksby IPCC Sector

-500

0

500

1000

1500

2000 Land Use ChangeWasteAgricultureIndustrial ProcessesEnergy

1990

1991

1992

1993

1994

1995

1996

1997

1998

The majority of theemissions in theEnergy sector comefrom combustion offossil fuel of whichtransportation is onlyone part.

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U.S. GHG Emissions1998 Only

CO2

CO2 fromTransportationCH4

N2O

HFC,PFC,SF6

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U.S. GHG Emissions1998 Only

CarsSmall TrucksLarge TrucksBusesAircraftBoatsBunkerTrainsOther

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Aviation Bunker FuelCalculations

Aviation transportation– Tier I approach: The quantity of fuel purchased and

delivered within the United States provides an accurateestimate of the national CO2 emissions.

Start with the total jet fuel consumption– Determine International Bunker Fuel– Three components of Bunker Fuel:

1) Fuel used by U.S. flag carriers on international flights2) Fuel purchased by foreign flag carriers while at United States

airports3) International flights by the United States Military

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Aviation Bunker Fuel DataSource

Commercial International Bunkers– The Bureau of Transportation Statistics (BTS) produces

a monthly report (Form 41) entitled “Fuel Cost andConsumption”

– BTS data is supplied in gallons. The data must beconverted to heat content units: MMBtu/gallon.

– Let’s look at a sample calculation

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1998 Sample Calculation

U.S. Flag Commercial International Bunkers

Heat content jet fuel = (5.67 MMBtu/Barrel)(Barrel/42 gallons) = 0.135MMBtu/gallon

Calculation:(4,725,250,123 gallons used in round trip international flights)(0.135 MMBtu) =

637,908,767 MMBtu(637,908,767 MMBtu)(1Tbtu/1,000,000 MMBtu) = 637.9 TBtu

½ International Jet Fuel consumption (outbound flight only) = 319 TBtu (rounded)

(Inbound leg of round trip flights assumed to have purchased fuel at overseasairport.)

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1998 Sample Calculation

Foreign Flag Commercial InternationalBunkers

Total expenditure Foreign Flag carriers at U.S. airports = $7,107 MillionPercentage of total expenditure spent for fuel and oil = 24%($7,107 x106)(0.24) = $1,706,000,000 Million spent on fuel

Fuel cost (cent/gal) = $0.5435($1,706,000,000)/($0.5435) = 3,138,914,443 gallons fuel

(3,138,914,443 gallons)(0.135 MMBtu/gallon) = 423,753,449 MMBtu(423,753,449 MMBtu)/1,000,000 MMBtu/TBtu = 424 TBtu

Bunker fuel sold to Foreign Flag Carriers (424 TBtu)

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Military Bunkers

Determine International Bunker Fuel– Three components of aviation bunker fuel:

1) Fuel used by domestic flag carriers on internationalflights

2) Fuel purchased by foreign flag carriers while atUnited States airports

3) International flights by the United States military– Now let’s look at the military aviation bunker fuels

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1998 Sample CalculationMilitary Aviation Bunker Fuel

Data on fuel delivered to the military within the United Statesis provided from unpublished data by the Defense EnergySupport Center under the Defense Logistics Agency

Heat content jet fuel = (5.67 MMBtu/Barrel)(Barrel/42 gallons) =0.135 MMBtu/gallon

(501.67x106 gallons)(0.135 MMBtu) = 67,725,450 MMBtu(67,725,450 MMBtu)(1Tbtu/1,000,000 MMBtu)

= 68 TBtu Military bunker fuel (rounded)

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1998 Sample Calculation

Reported in Table 2-33 of the U.S. NationalInventory

Domestic Flag International bunker fuel (319 TBtu) + Bunker fuel sold to Foreign Flag Carriers (424 TBtu)

+ Military Bunker fuel (68 TBtu)

International Bunker Jet Fuel Use = 811 TBtu

Now multiply fuel use by carbon content of fuel and assumed oxidation fraction:

International Aviation Bunker Fuel CO2 Emissions =(811Btu/1000)(19.33MMTCE/Tbtu)(0.99) = 15.5 MMTCE

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Carbon Dioxide Emissions fromAviation Transport by Mode

0

50

100

150

200

250

300

1990

1992

1994

1996

1998

Military Bunkers

Aviation Bunkers

Military Domestic

Other Jet Fuel Use

General Aviation

Commercial AirCarriers

Tera

gram

s of C

arbo

n D

ioxi

de E

quiv

alen

ts(T

gCO

2 Eq

)

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Aviation Fuel Breakout by Mode– 1998 only

55%

21%

2%

8%

10%4%

Commercial AirCarriersAviation Bunkers

Military Bunkers

Military Domestic

Other Jet Fuel Use

General Aviation

77% Domestic

23% Bunker

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Marine Bunker Fuel CalculationsMarine transportation Tier I approach:

The quantity of fuel purchased and delivered within theUnited States provides an accurate estimate of thenational CO2 emissions.

Ocean-going ships use two primary types offuel:

Diesel and Residual fuel oil

Three components of Bunker Fuel:1) Fuel used by domestic flag carriers on international voyages2) Fuel purchased by foreign flag carriers while at United States

ports3) International deployments by the United States Military

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Carbon Dioxide Emissions fromMarine Transport

0

20

40

60

80

100

120

140

1990

1992

1994

1996

1998

Int'l Bunker - ResidualInt'l Bunker DieselInt'l Bunker MilFrt - residPersonal Motor GasFrt- Diesel

Tera

gram

s of C

arbo

n D

ioxi

de E

quiv

alen

ts(T

gCO

2 Eq

)

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U.S. GHG Emissions1998 Only

CarsSmall TrucksLarge TrucksBusesAircraftBoatsBunkerTrainsOther

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Marine Bunker Fuel

Commercial International Bunkers– Assumed all the residual fuel oil is used by vessels.– We could not assume all diesel was used at sea.– The U.S. Department of Commerce from Foreign Trade

Division, Bureau of the Census Provided the data in areport titled: Report of Bunker Fuel Oil Laden onVessels Cleared for Foreign Countries (Form –563)

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1998 Sample CalculationCommercial International Bunkers

Distillate Fuel (627,282,000 gallons distillate fuel)(0.1387MMBtu/gallon) =

93,904,115,540.57 MMBtu(87,004,013.4 MMBtu)(1TBtu/ 1,000,000 MMBtu) =

87.00 TBtu

Residual Fuel (3,973,566,000 gallons residual fuel)(0.1497MMBtu/gallon) = 594,842,830.2 MMBtu

(594,842,830.2 MMBtu)(1TBtu/1,000,000 MMBtu) = 594.8 TBtu

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Military Bunkers

Determine International Bunker FuelThree components of Bunker Fuel:

1) Fuel used by domestic flag carriers on internationalvoyages

2) Fuel purchased by foreign flag carriers while atUnited States ports

3) International deployments by the United StatesMilitary

Now let’s look at the Military Marine BunkerFuels

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Military International BunkerFuels

Heat content marine fuel = (31,880,000 gallons Navy MGO*)(0.1387MMBtu/gallon) = 4,421,756 MMBtu MGO

(4,421,756 MMBtu)/(1TBtu/1,000,000 MMBtu) = 4.42 TBtu

(474,230,000 gallons Navy F76*)(0.1387 MMBtu) = 65,775,701 MMBtu(65,775,701 MMBtu)(1TBtu/1,000,000 MMBtu) = 65.78 Tbtu

Military Marine Distillate Bunker fuel = 70.2 TBtu

*Navy MGO and F76 are distillate fuels.

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Breakout of Marine TransportFuel – 1998

17%

19%

9%5%6%

44%

Freight - DieselPersonal - Motor GasFreight - Residual Int'l Bunkers MilitaryInt'l Bunkers - DieselInt'l Bunkers - Residual

55% International45% Domestic

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Conclusion

Total U.S. CO2 from Fossil Fuel Combustionin 1998 was 1,468.2 MMTCEInternational Aviation Bunker Fuel =

15.5 MMTCE (about 1% of total CO2)

International Marine Bunker Fuel =15.8 MMTCE (about 1% of total CO2)

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CONTACT

• Gail Bruss, Office of the Chief of NavalOperations, (703) 602-7871,Bruss.Gail@hq.navy.mil

• Wiley Barbour, Environmental ProtectionAgency, (202) 564-3999,Barbour.Wiley@epamail.epa.gov